This invention relates to certain elastomeric blends containing a sol of an uncrosslinked elastomer and a gel of a crosslinked copolymer of ethylene with carbon monoxide and with one or more ethylenically unsaturated monomers copolymerizable therewith.
Many commercial elastomers, for example, ethylene/vinyl acetate copolymers, ethylene/methyl acrylate copolymers, and chlorosulfonated polyethylene are soft and sticky and thus difficult to process in ordinary industrial equipment and, unless specially surface treated or compounded, also difficult to ship or store. It is well known that the processability of soft elastomers may be improved by thoroughly blending them with a gel polymer, for example, a crosslinked elastomer. While blending such different types of elastomers in a latex presents no difficulty, polymer latices are not always available. When blend components are not in latex form, it is not attractive to specially prepare latices having suitable consistencies, to handle the resulting large volumes, and to go through the extra steps of isolating the blend from the latex and drying. However, blending uncured, dry, soft elastomers with dry, cured elastomers is very difficult, so that a good dispersion of one elastomer in the other cannot be obtained.
There is, therefore, a need in the art for a method which would permit effective dry blending of such elastomeric components.